Every other SEO task from content to conversion depends on the selected keywords. But within different industries, different keywords will convert better and if a keyword doesn't generate customers then it doesn't make sense to target it. The trick is to find this information out before you start shoveling money into your campaign. We put all prospective keywords through a conversion quality assesment to gauge the quality of the keyword.
Search engines decide which pages are most likely to be useful and sort them to appear first so it's important that your search terms match up to your products and offerings. Geo-Relevancy can be even more important, depending on your campaign. With Geo-Relevancy, you can target specific cities and states where your services can be provided.
People want to target the keywords that have the most volume but these keywords are also the most difficult to rank for. The easiest keywords to target have no traffic either, though, causing a conundrum. The answer is balance. We're experienced with picking keywords that have a good volume but low difficulty to give you maximum effectiveness.